On Sunday, corporate taxes in Japan dropped to 38%, making America's 39.2% rate the world's highest and well above the average of 25.4% for developed nations, according to the Organization for Economic Cooperation and Development.

Amid the broader issue of reforming the tax code, corporate tax rates have already been a hot-button issue on the campaign trail: President Obama has proposed lowering the top rate to 28% while Mitt Romney's plan would drop it to 25%. Anti-tax crusader Grover Norquist says dropping corporate rates to 25% is just "the first bite at the apple." America's new standing as the world's top corporate tax regime is adding further fuel to the partisan fire.